Valve-operating mechanism



Fatented May 6, 1924,

DORSEY F. AS BURY, OF WASHINGTON, DISTRICT OF COLUMBIA.

vnnveornimrme MECHANISM.

Application filed April 19, 1920. Seriallfi'o. 374,998.

To all whom it may concern:

Be it known that I, DORSEY F. ASBURY, a citizen of the United States, residing at Washington, in the District of Columbia,

have invented certain new and useful Improvements in Valve-Operating Mechanism, of which the following is a specification.

My invention relates to valve operating mechanism and is similar in purpose to my former application filed Feb. 21, 1920, serially numbered 360387 and a companion application for like improvements filed of even date with this application, its aim being to provide further improvements 'in such mechanisms whereby noise, friction, lubrication and the necessity for adjustment of parts is eliminated.

The invention consists in the novel features of construction, combination and arrangement of parts as will be hereinafter more fully described, illustrated in the accompanying drawings and defined by the appended claims.

In the drawings Fig. 1 is a vertical section through an internal combustion engine showing the application of my invention thereto with the parts in an exaggerated normal position;

Fig. 2, a similar view showing the position of the parts when the valve is opened;

Fig. 3, a view similar to Fig. 1 showing a slightly modified construction; and

Fig. 4:, a view similar to Fig. 1 of a further modified construction.

Referring to the drawings in detail, particularly to Figures 1 and 2, A designates, generally, an internal combustion engine of the valve-in-head type including a cylinder 10, and cylinder head ll. Seating on the head is a puppet valve including a stem 16 which projects through and above the cylinder head and has associated therewith a spring 17 holding the valve normally to its seat. Disposed in operative relation to the valve stem is a tappet rod 18, while bridging the upper ends of the valve stem and tappet rod is a lever arm 19. Convexed surfaces are provided on the lever arm and these surfaces are adapted to roll on the upperflat ends of the valve stem and tappet rod during operation of the mechanism whereby friction is eliminated.

My invention consists in the provision of a toggle arrangement associated in any convenient or preferred manner with the parts above enumerated to maintain the parts of the mechanism in contact whereby noise is eliminated, and as I have provided a toggle which is anti-frictional in its operation, the necessity'for lubrication of the mechanism is eliminated. As. indicated in the drawings this toggle arrangement is not limited to any particular association with the remaining parts of the mechanism, as it functions may be accomplished equally as well in various locations. Preferably, however, it is designed, as illustrated in Fig. 1 to provide a fulcrum for the lever arm.

The said toggle fulcrum for the lever arm consists of a pair of links 20 and 21, the former being looped over the lever arm and seating in a suitable saddle formed at an intermediate point in the upper face of the lever arm and the latter engaging a pin or roller 22 carried by a bracket 23 suitably secured to the cylinder head. The links are relatively connected and their connection is rendered antifrictional by providing a convexed surface onone of them engaging a flat surface on the other. In a similar manner the connectionv between the link 20 and the lever arm is also rendered antifrictional. Link 21 may be openon' one side to facilitate assembly of the mechanism. 7

An arrangement such as the foregoing forms a toggle device and provides a fulcrum for the lever' arm all parts of which roll with respectto their associated parts when the mechanism is in operation, and friction is thereby eliminated. j

. It is apparentthat if the links are rotated from their outer ends the distance between their outer ends will progressively decrease proportionately to the degree of such rotation and in the arrangement illustrated rotation of the links will result in the lever arm being forced down in contact with the tappet rod and valve stem. I provide constantly acting yieldable means in the nature of a leaf spring 24c secured at one end, to the bracket 19 and at its other end engaging the link 21 adjacent to its point of connection with the link 20 and exerting a force against said link tending to break the toggle and thus maintain the parts of the mecha-.

nism in contact at all times during the absence of the operating force of the mechanism.

In Fig. 3 of the drawing I illustrate one method in which a coil spring may be utilized to perform the function of the leaf spring 24. The coil spring 24' may have one end secured to the link 21 and its other end secured to the lever arm 19. By such an arrangement either a tension spring or a compression spring may be utilized.

Fig. 4 illustrates one manner of associating a toggle arrangement with a usual type of pivoted rocker arm other than at its fulcrum to accomplish the purposes referred to. Here a link 25 is connected at one end to the rocker arm and at its other end to the tappet rod, the latter because of its lateral play constituting the second member of the toggle. A coil spring 26 between the ling and the bracket supporting the rocker exerts a force constantly tending to straighten the toggle and thereby maintain the parts of the mechanism in contact.

The amount of disalinement of the links when in their normal position will be very slight and is considerably exaggerated in the drawings. Upon upward movement of the tappet rod, however, irrespective of the relative position of the links, the force of the spring 24, 24 or 24 will be overcome and said spring will yield until the toggle is substantially straightened, the toggle then acting positively as an element of the mechanism to cause the same to rock and force the valve down and open.

Various modifications may be made in the structures I have disclosed without departing from the spirit or scope of my invention as claimed.

I claim 2- l. A valve operating mechanism including a toggle joint, and means normally maintaining said toggle joint broken thereby to maintain the parts of the mechanism in contact, the elements of said toggle joint having direct rollable contact with each other.

2. A valve operating mechanism including lever arm, a toggle joint, and means normally maintaining said toggle joint broken thereby to maintain the parts of the mechnism in contact, one element of said toggle joint having direct rollable contact with the lever arm.

A valve operating mechanism for engines including a toggle joint, a member on the engine and means normally maintaining said toggle joint broken thereby to maintain the parts of the mechanism in contact, one element of said toggle joint having direct rollable contactwith the member on the engine.

t. A valve operating mechanism including a toggle joint; and means normally maintaining said toggle joint broken thereby to hold the elements of the mechanism in contact, the elements of said toggle joint having direct rollable contact with each other and, respectively, having direct rollable contact with associated parts of the mechanism.

5. A valve operating mechanism including a lever arm,- a toggle joint fulcrum for said lever arm, and means normally maintaining said toggle joint fulcrum broken thereby to maintain the parts of the mechanism in contact, said toggle joint fulcrum including a pair of members one of which has direct rollable contact with the lever arm.

6. A valve operating mechanism for engines including a lever arm, a toggle joint fulcrum for said lever arm, and means normally maintaining said toggle joint fulcrum broken thereby to maintain the parts of the mechanism in contact, said toggle joint fulcrum including a pair of members one of which has direct rollable connection with the engine.

'7. A valve operating mechanism including a lever arm, a toggle joint fulcrum for said lever arm, and means normally maintaining said toggle joint fulcrum broken thereby to maintain the parts of the mechanism in contact, said toggle joint including a pair of members having direct rollable contact with each other.

8. A valve operating mechanism for engines including a lever arm, a toggle joint fulcrum for said lever arm, and means normally maintaining said toggle joint fulcrum broken thereby to maintain theparts of the mechanism in contact, said toggle joint including a pair of members having direct rollable contact with each other and, respectively, having direct rollable contact with the lever arm and with a fixed part of the engine.

In testimony whereof I hereunto aflix my signature in the presence of two witnesses.

DORSEY F. ASBURY.

Witnesses:

CARROLL BAILEY, FLORENCE A. BLINK. 

